1
|
Loss of Thymine DNA Glycosylase Causes Dysregulation of Bile Acid Homeostasis and Hepatocellular Carcinoma. Cell Rep 2021; 31:107475. [PMID: 32268085 DOI: 10.1016/j.celrep.2020.03.039] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Revised: 01/14/2020] [Accepted: 03/12/2020] [Indexed: 12/31/2022] Open
Abstract
Thymine DNA glycosylase (TDG) is a nuclear receptor coactivator that plays an essential role in the maintenance of epigenetic stability in cells. Here, we demonstrate that the conditional deletion of TDG in adult mice results in a male-predominant onset of hepatocellular carcinoma (HCC). TDG loss leads to a prediabetic state, as well as bile acid (BA) accumulation in the liver and serum of male mice. Consistent with these data, TDG deletion led to dysregulation of the farnesoid X receptor (FXR) and small heterodimer partner (SHP) regulatory cascade in the liver. FXR and SHP are tumor suppressors of HCC and play an essential role in BA and glucose homeostasis. These results indicate that TDG functions as a tumor suppressor of HCC by regulating a transcriptional program that protects against the development of glucose intolerance and BA accumulation in the liver.
Collapse
|
2
|
Shen G, Shen H, Zhang J, Yan Q, Liu H. DNA methylation in Hepatoblastoma-a literature review. Ital J Pediatr 2020; 46:113. [PMID: 32758256 PMCID: PMC7409486 DOI: 10.1186/s13052-020-00877-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 07/29/2020] [Indexed: 12/19/2022] Open
Abstract
Hepatoblastoma (HB) is the most common malignant liver tumor in children. Abnormal activation of the Wnt/β-catenin signaling pathway plays an important role in the formation and development of HB. Genes in HB show a global hypomethylation change, accompanied by hypermethylation of specific tumor suppressor genes (TSGs). This article reviews the hypermethylation changes in several TSGs, such as RASSF1A, SOCS1, APC, HHIP, and P16, and analyzes the pathways and mechanisms of TSGs regulating gene expression. The role of the methylation-regulating enzymes DNA methyltransferases (DNMTs) and ten-eleven translocation (TET) family members enzymes in the methylation changes of HB was analyzed, and it was speculated that the occurrence of HB is partly due to the obstruction of liver differentiation in the early stage of differentiation. The origin cells may be incompletely differentiated hepatocytes remaining in the liver of children after birth. Therefore, further studying the role of methylation regulating enzymes in methylation changes in HB is a promising future research direction.
Collapse
Affiliation(s)
- Gang Shen
- Pediatric Surgery Department, Weifang Peoples' Hospital, Weifang, China
| | - Hongyu Shen
- Ultrasound Department, Weifang Haifushan Hospital, Weifang, China
| | - Jing Zhang
- Pediatric Surgery Department, Weifang Peoples' Hospital, Weifang, China
| | - Qingtao Yan
- Pediatric Surgery Department, Weifang Peoples' Hospital, Weifang, China
| | - Huixian Liu
- Dermatology Department, Weifang Peoples' Hospital, No. 151, Guangwen Street, Kuiwen District, Weifang, 261041, China.
| |
Collapse
|
3
|
Castiglioni V, Radaelli E. Spontaneous pulmonary co-metastasis of hepatoblastoma arising within a hepatocellular carcinoma in an aged C57BL/6J mouse. J Toxicol Pathol 2018; 31:195-199. [PMID: 30093789 PMCID: PMC6077162 DOI: 10.1293/tox.2017-0067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 04/20/2018] [Indexed: 02/03/2023] Open
Abstract
Murine hepatoblastoma (HB) is a rare spontaneous tumor with controversial histogenesis. It mainly occurs in aged males, frequently in close association with preexisting hepatocellular neoplasms. The present work describes a spontaneous HB arising within a hepatocellular carcinoma (HCC) in a 22-month-old male C57BL/6J mouse. The mouse also developed pulmonary co-metastases with either tumor components physically associated within the same metastatic foci. Microscopically, the HB consisted of a densely cellular neoplastic growth composed of palisades and perivascular pseudorosettes of poorly differentiated primitive cells, with a scant amount of cytoplasm, elongated hyperchromatic nuclei, and a high mitotic rate, whereas the hepatocellular carcinoma was composed of solid areas of neoplastic hepatocytes. Both in primary tumors and their metastases, β-catenin immunohistochemistry revealed a strong nucleocytoplasmic signal in HB cells, while neoplastic hepatocytes displayed a delicate membranous staining pattern. These findings suggest that the Wnt/β-catenin oncogenic pathway is upregulated in murine HB but not in the co-existing HCC, thus providing some insights into their divergent pathogenesis. Coexisting murine HB and HCC have been demonstrated to be completely distinct entities including origin, mutational landscape, and molecular profile. In this context, they might be regarded as collision tumors because of their intimate association, unique histologic features, and distinct immunohistochemical patterns. Nevertheless, the nature of their coevolution and progression to a co-metastatic phenotype reflects a close interdependence and support the overall idea that HB's origin and progression might be promoted by not otherwise specified paracrine stimuli provided by the concurrent hepatocellular tumor (the so called "interaction theory").
Collapse
Affiliation(s)
| | - Enrico Radaelli
- Comparative Pathology Core, Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, 3900 Delancey Street, Philadelphia, PA 19104-6051, U.S.A.,VIB Center for the Biology of Disease and KU Leuven Center for Human Genetics, Herestraat 49, Leuven 3000, Belgium
| |
Collapse
|
4
|
Combined effects of PLK1 and RAS in hepatocellular carcinoma reveal rigosertib as promising novel therapeutic "dual-hit" option. Oncotarget 2017; 9:3605-3618. [PMID: 29423069 PMCID: PMC5790486 DOI: 10.18632/oncotarget.23188] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Accepted: 12/03/2017] [Indexed: 02/07/2023] Open
Abstract
Inhibition of RAS-RAF-ERK-signaling is a major mechanism mediated by the multi-kinase inhibitors sorafenib and regorafenib, the only effective therapeutic approaches for advanced hepatocellular carcinoma (HCC). This underlines the importance of RAS-RAF-ERK-signaling in HCC. Most RAS isoforms were not yet described to play crucial roles in HCC. However, several studies indicate that the HRAS isoform can function as potent oncogene in HCC, but pharmacologic RAS inhibition has not yet been investigated. Moreover, the cell cycle promoting polo-like kinase 1 (PLK1) is an increasingly recognized therapeutic target in HCC that can be activated by RAS-RAF-signaling. A recently developed small molecule inhibitor, ON-01910 ("rigosertib", RGS), was shown to interfere with both RAS- and PLK1-signaling. The aim of this study was to analyze the effects of RGS in HCC and to assess PLK1 and HRAS expression in HCC. RGS treatment reduced cell proliferation and induced cell cycle arrest in human HCC cell lines in vitro. Moreover, RGS strongly inhibited both ERK- and AKT-activation in HCC cells, indicating disruption of RAS-signaling. Analysis of HCC patient data showed that PLK1 and HRAS expression levels are upregulated during HCC development and in advanced HCC, respectively. High expression levels of PLK1 significantly correlated with poor patient survival. Moreover, high expression of both PLK1 and HRAS revealed combined effects on patient outcome. This underscores the importance of these genes and associated pathways in HCC. We newly demonstrate the therapeutic potential of RGS in HCC by inhibition of both PLK1 activation and major RAS-pathways, revealing a novel therapeutic "dual-hit" approach for HCC.
Collapse
|
5
|
Comerford SA, Hinnant EA, Chen Y, Bansal H, Klapproth S, Rakheja D, Finegold MJ, Lopez-Terrada D, O'Donnell KA, Tomlinson GE, Hammer RE. Hepatoblastoma modeling in mice places Nrf2 within a cancer field established by mutant β-catenin. JCI Insight 2016; 1:e88549. [PMID: 27734029 DOI: 10.1172/jci.insight.88549] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Aberrant wnt/β-catenin signaling and amplification/overexpression of Myc are associated with hepatoblastoma (HB), the most prevalent type of childhood liver cancer. To address their roles in the pathogenesis of HB, we generated mice in which Myc and mutant β-catenin were targeted to immature cells of the developing mouse liver. Perinatal coexpression of both genes promoted the preferential development of HBs over other tumor types in neonatal mice, all of which bore striking resemblance to their human counterparts. Integrated analysis indicated that tumors emerged as a consequence of Myc-driven alterations in hepatoblast fate in a background of pan-hepatic injury, inflammation, and nuclear factor (erythroid-derived 2)-like 2/Nrf2-dependent antioxidant signaling, which was specifically associated with expression of mutant β-catenin but not Myc. Immunoprofiling of human HBs confirmed that approximately 50% of tumors demonstrated aberrant activation of either Myc or Nfe2l2/Nrf2, while knockdown of Nrf2 in a cell line-derived from a human HB with NFE2L2 gene amplification reduced tumor cell growth and viability. Taken together, these data indicate that β-catenin creates a protumorigenic hepatic environment in part by indirectly activating Nrf2 and implicate oxidative stress as a possible driving force for a subset of β-catenin-driven liver tumors in children.
Collapse
Affiliation(s)
| | - Elizabeth A Hinnant
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Yidong Chen
- Department of Epidemiology and Biostatistics and.,Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Hima Bansal
- Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | | | - Dinesh Rakheja
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | | | - Dolores Lopez-Terrada
- Department of Pathology, and.,Department of Pediatrics, Baylor College of Medicine, Texas Children's Hospital, Houston, Texas, USA
| | - Kathryn A O'Donnell
- Department of Molecular Biology.,Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Gail E Tomlinson
- Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA.,Department of Pediatrics, University of Texas Health Science Center at San Antonio and Greehey Children's Cancer Research Institute, San Antonio, Texas, USA
| | - Robert E Hammer
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| |
Collapse
|